Evaporative condenser apparatus and liquid disperser unit therefor



July 1, 1958 T. w. CARRAWAY 2,341,369

EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR 8 Sheets-Sheet 1 Filed Aug. 17, 1953 Fig.1.

INVENTDR 7% A A TTORNEYS July 1, 1958 T. w. CARRAWAY 29841 369 EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR Filed Aug. 17, 1953 8 Sheets-Sheet 2 57 7720ma5M6a7'rau/a3 a, ATTORNEYS July 1, 1958 T. w. CARRAWAY EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR 8 Sheets-Sheet 3 Filed Aug. 17, 1953 IN VE N TOR 750m? All kzrrauxay 600M,

/AM. la ATTO R N EYS Jufly 1, 1958 T. w. CARRAWAY 3 v EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFQR Filed Aug. 17, 1953 8 Sheets-Sheet 4 Fig.7,

7750mm 12 Uarraway fi 5M,W; (1W Z6 46 47 45 A vs July 1, 1958 T. w. CARRAWAY 2,841,369

EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR Filed Aug. 1'7, 1953 8 Sheets-Sheet 5 J11 1002 FL .11. {100A Q INVENTOR [5 1 BY 59%; /a/M ATTORNEYS mamas 0 Uarra way July 1, 1958 T. w. CARRAWAY 59 EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR Filed Aug. 17, 1955 8 Sheets-Sheet 6 A l-J51 3 J05 4 Q INVENTOR ffiomcz; 6U. Carrazaay ATTORNEYS July 1, 1953 T. w. CARRAWAY 2,341,369

EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFQR Filed Aug. 17. 1953 8 Sheets-Sheet 7 15.9 20 F 16 23 J41 1 J4] Z2 123a 1001) J 42 I J40 i 22.5 55 i J19 J45 245 1136 146 J41 J45 18. 4" 142 142 TOR mamas [d Carmwczy ATTORNEYS July 1, 1958 T. w. CARRAWAY 2,841,359

EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR 8 Sheets-Sheet 8 Filed Aug. 17, 1953 /z mas 01 Carina/a ATTORNEYS 2,841,369 Fatented July 1, 1958 ice EVAPORATIVE CONDENSER APPARATUS AND LIQUID DISPERSER UNIT THEREFOR Thomas W. Carraway, Dallas, Tex.

Application August 17, 1953, Serial No. 374,565

4 Claims. (Cl. 257-37) This invention relates to evaporative condenser apparatus, and to liquid disperser units especially suited for use in connection with such apparatus.

This application is a continuation-in-part of my copending application Serial No. 72,406, filed January 24, 1949, and now abandoned.

Evaporative condensers have gained favor since their introduction in the heat exchange field some time ago. The general construction and mode of operation of conventional apparatus of this kind are well known. Usually, a blower is arranged to cause an air stream to flow over a condenser coil unit through Which the gas to be cooled is passed, and evaporative liquid, e. g. water, is introduced into the air stream, and sometimes is deposited upon the coil unit so as to extract. from the air and from the coil unit the heat required to evaporate the liquid. Such equipment has the advantage of eliminating the substantial expense of providing a source of cool Water which is wasted after use in condensing, or a cooling pond or tower for cooling the condensing water when the latter is recirculated.

The efficiency and economy of operation of evaporative condensers of the class to which the present invention relates depend largely upon the eifectiveness with which the evaporative liquid is dispersed or diffused in the air stream. in the past, the dispersion or dififusion has been accomplished as well as possible, by then known methods and equipment, most commonly by spraying the liquid from nozzles. This has resulted in practical difiiculties, principally the necessity for servicing the nozzles frequently to remove stoppages, or scale encrustation or deposits. This is objectionable not only because of the servicing costs involved, but also because of the inconvenience and other obvious disadvantages of placing the equipment out of operation for servicing.

An object of the present invention is to provide evaporative condenser apparatus including a novel unit comprising an air moving means, a heat exchanger, and an evaporative liquid disperser means so constructed and arranged as to eliminate the outstanding difliculties heretofore encountered in the use of known evaporative condenser apparatus.

Another object of the invention is to provide evaporative condenser apparatus of the kind referred to in which the liquid disperser means is of novel and improved construction and is capable of operating continuously, with out service shut-downs, for producing a well dispersed or diffused mass of liquid in the air stream, and depositing a thin film of liquid on the heat exchanger coils.

Another object of the invention is to provide such evaporative condenser apparatus in which the liquid disperser means is so constructed and arranged with respect to a heat exchanger coil or other unit as to direct successive but merging phases of dispersed liquid onto the unit in a graduated distribution varying from a dispersion of relatively large drops which impinge on the upper part of the unit to a fineiydivided 03 or mist vwhich. is

caused to envelop the lower part of the unit, whereby substantially the entire heat exchanger unit will be maintained wet, and liquid from the drops impinging on the upper part of the unit will run down over and thereby will wash the surfaces of the unit from top to bottom.

Another object of the invention is to provide a liquid disperser unit of novel and improved construction including rotatable impellers for producing the graduated distribution referred to.

Another object of the invention is to provide an improved liquid disperser unit comprising rotatable impellers of novel construction, and deflectors associated with the impellers for controlling or determining the zone in which the dilfusion of liquid is produced.

A further object of the invention is to provide a disperser unit of the character referred to including an improved arrangement for insulating and cooling a driving motor for the disperser element or elements.

Other objects of the invention will become apparent from a reading of the following description, the appended claims, and the accompanying drawings.

Figures 1 to 10 inclusive show one embodiment of the invention, and in these figures:

Figure l is a vertical, longitudinal sectional view of apparatus embodying the invention, on the line 11 of Figure 2;

Figure 2 is a horizontal sectional view on the line 2-2 of Figure 1;

Figure 3 is a transverse vertical sectional view on the line 3-3 of Figure 1;

Figure 4 is a detail, vertical sectional view of liquid dispersing apparatus constructed in accordance with the invention, drawn on an enlarged scale;

Figure 5 is a horizontal sectional view on the line 55 of Figure 4, one impeller disk and deflector being omitted;

Figure 6 is an end elevation showing the dispersing apparatus as viewed from the right of Figure 4;

Figure 7 is a vertical sectional view on .the line 77 of Figure 4;

Figure 8 is a fragmentary vertical sectional View on the line 8-8 of Figure 4;

Figure 9 is a detail end elevational view of a liquid deflector; and

Figure 10 is a wiring diagram showing a control circuit and control devices for regulating the operation of the apparatus.

Figures 11 to 23 inclusive show another embodiment of the invention, and in these figures:

Figure 11 is a horizontal, longitudinal sectional view of a second form of apparatus embodying the invention on the line 1l.-11 of Figure 12, some parts being shown in plan;

Figure 12 is a vertical sectional view on the line 1212 of Figure 11, some parts being shown in elevation;

Figure 13 is a transverse vertical sectional view on the line 13-13 of Fi ure 12, certain parts being shown in elevation;

Figure 14 is a vertical sectional view on the line 14-14 of Fi ure 12; certain parts being shown in elevation;

Figure 15 is a fragmentary bottom plan view of the Figure 19 is an end elevational view of the disperser unitshown inFigures 16,17 and 1,8;

Figure 20. is a transverse vertical sectional view on the line 2t)20 of Figure 16;

Figure 21 is a fragmentary vertical sectional view on the-IineZI-FZI of Figure 17; i

:Figure' 22 is a 'vertical'section on the line 22+-Z2 of Figure-11,6; and a Figure 23. is a vertical section on the line.;.23-'-23. of Figure. 16'. l

The form of apparatus shown in Figures 1 to 10 inelusive includes a substantially straight horizontal duct A in which are mounted a heat exchanger B, a fan C, and aliquid disperser unit generally designated D. The parts are so arranged that the fan C, located adjacent the. right-hand end of the duct, as viewed in Figures 1 and 2, causes a. stream of air to flow through the'duct past the air chamber immediately above the disperser unit D, and over. and through theiheat exchanger B, the air then passing out through the left-hand end of the duct. A. Before the air encounters the heat'exchanger B, it is cooled by evaporative liquid thrown upwardly and. dispersed or difiused by the disperser D so as more eifectively to. extract heat. from the. heat exchanger B. Preferably,. e. action of the disperser D is so. regulated or controlled that. in addition toproducing a volume of diffused. liquid between. the fan C and the heat exchanger B.,. it. also. deposits. a very thin film of liquid upon the surfaces of theheat exchanger B so as to augment the. cooling. operation by evaporation ofliquid fromtheheatexchanger. V

The duct A may be of any suitable construction; In the for-ml shown, it; is constructed of sheet .metal suitably reinforced at its seams and corners. shock insulators 1 of rubber or. similar cushioning material are attached to the top. and bottom walls at the four corners of each. for mounting either under a ceiling or on a floor, and preferably a screen. 2 of wire mesh of equivalent reticulated material is mounted at the intake end of the. duct for preventing the ingress of particles of solid foreign matter. Eliminators 3 are mounted at the left-hand or air discharge end of the duct for'preventing the outflow of any unevaporated droplets of liquid which maybe carried in the. air stream past the heat exchanger B- The eliminatorsare so formed and inclined that droplets of liquid which they intercept will drain back into a pan or reservoir 4 mounted in the bottom of the duct A. a

The fan; C is'driven by an electric motor 5 which is mounted upon a support comprising a platformo carriedby legs 7: extending; upwardlyfrom, the bottom of the. pan; 4;. 1A; partition 8 extending. across the duct in the central plane of the fan C is formed with an opening 8?- w ich receives the. fan blades'with suitable operating clearance. V

11 h at: exchanger B, is. shown as. comprising a, condenser tube or; coil unit; including: an inlet. connection 9 adaptedto be. connected to, a Source. of gas or other 7. fluid medium to be cooled, and to lead such medium 'to. a top header. 1h. Extendingrfrom; the top header 1d are four pipes. 11' formed respectively as coils, and extending back and forth so as collectively to .cover the major part of a cross section of the duct, the lower crosses of the pipes 11 ending at and being connected to a. bottom; header l2. Fluid cooled by passage through the pipes 511 'flows from the bottomheader 12 through a; pipe 13; which extends diagonally across and toward the right-hand end of the duct,'where, it is connected to a horizontally disposed supplemental heat exchanger or cooling unit 1 .4 which is located directly under the coil'assembly 1i and just above the reservoir ortank l-"SQ as to underlie the partof the 'duct A included between the fan C and the heat exchange coil unit 11.

the discharge end of; the, duct andthen, downwardly? as Cushions or at 14 for communication; wi h. a; lower; layer of; coi1s..75

l4? which extend towardthe. air-en rance end oi the duct A and terminate in an exit pipe 15.

In operation, fluid to be condensed or cooled is introduced through the inlet 9 into the heat exchanger B so as to flow first through the coils 11 in which it is cooled by air forced through the duct A 'by the fan C. Under certain load conditions the cooling effect of the air alone may be sufiicient to bring about the desired condensing. or cooling of the fluid passed through the heat exchanger B. l

Under heavier load conditions where a greater cooling er'iect is required, the disperser'D is operated toct'eate a mist or fog of dispersed or difii'used' evaporative liquid in the stream of air approaching the heat exchanger B, and so as to deposit a film of evaporative liquid on the Coils ll. Evaporation of the liquid in the air stream cools the air itself so as to render its heat absorptivecapacity. greater; and evaporation of thefilm; of liquid from .thecoilsill stilt. further augments thecooling' capacity;

The. surplus evaporative liquid, e. gwater, discharged bythe disperser; D and dropping, unevaporated, from the coil assembly 11, and from the ductfspace betweenthe fan C and. the. coils: .11, willfenvelop the supplemental cooler coils-.ild. and. extract. additional heat. from. the: medium flowing from, the .coil unit .11 through; the coils 141.

The overall capacity and operating efficiency of the; ap:

paratns-depends very largely: upon thev effectiveness with. p which evaporative liquid isdispersedin theairstream. and. deposited. in. thin. film. form .onthe. exchanger coilsl ll;

In. accordance withthe presentlinvention, the. dispersing; apparatus D, which performs. this important function, isv constructed as .a compact .unitwhichcan. be manufactured and ass mbled, in unit formin afactory where the neces sary care can be given toassembling. the parts. intheir proper relationshi s, The unitv so. constructed and as.-

sembled may then; easily be mounted within a duct when the whole apparatus is set upon assembled. either in an assembly plant, orone construction job location.

In its preferredjform the dispersing unitDincludes: a. base 16 adapted to be mounted upon a. stand or bracket 16 supported uponthe bottomof the pan 4. The base 16 isformed at, its, opposite euds with spaced. openetop receptacles 17. between which is mounted a. liquidtight.

motor housing; 18, secured to the base by any' suitable means, such as screws 19. An electriomotor, generally designated 213, is mounted, within, the housing 1.8,, andis secured to the housing bottom by screws 21. The. motor itself includes an apertured; casing 22. provided. with; hearings 22 -22 through, which opposite ends of the motor shaft '23 extend, so as, to. project through openings 24. in the, end walls 25 and 25? of theouter housing 18'. The housing 18 is nearly filled with liquid dielectric, e-., g., good, quality insulating oil indicated at 26, in suflicient, quantity to. surround the motor 20 completely, andfill the motor casing, in order to. prevent. leakage of, the: di-v electric fromv thehousing- .18, the openings; 24 in the In assembling the disperser'unit', the right-hand end wall ZS 'of-the outer housing 18 is removed, the motor 20 is placed in thehousing 18' and secured there by the screws 21, and themotorconductors 28 are connected to the inner ends of th ef-connector posts 29 With the housing 18 positioned. with its: open. end up, the liquid dielectric; 26' is poured. into the housing and the right- Preferably a gasket 33 is interposedgbetween the housing. end: 7

hand endwalr ZS- is then secured in place.

and the end wall 25*, which may be held in place by screws 34.

In operation, the dielectric oil fills the open or apertured motor casing 22 and covers the motor rotor and stator winding, circulating in and out of the motor casing to transfer the heat generated by the motor to the housing 38, and thence to the water in the reservoir 4.

The receptacles 17, previously referred to, are formed with side openings 35 which are so positioned as to be below the level of the liquid in the pan 4 when the dispersing unit D is mounted in the pan, as shown in Figure 1, thus ensuring that liquid from the pan 4 will flow into the receptacles 17 so as to maintain them filled to substantially the same level as the level of liquid in the pan 4. The evaporative liquid is picked up from the receptacles l7 and thrown transversely with respect to the direction of air flow, and also generally in the direction of air flow by impeller means comprising disks 36 mounted respectively on opposite ends of the shaft 23 and extending below the tops of the receptacles 17 so that the bottom portions of the disks will be partly submerged or immersed in liquid in the receptacles. The motor 20 drives the disks in the direction of the arrow a in Figure l at such high speed as to throw the evaporative liquid vertically into the duct A, and also generally in the direction of flow of air, that is, from right to left as shown in Figure 1. An important feature of the invention is the particular construction of the disks, which are so formed as to produce an evenly difiused or dispersed fog or mist of evaporative fluid with a minimum of incidentally formed or thrown droplets of liquid of such size as not to be readily evaporated. The disks 36 are mutually balanced, and are of identical form. As shown in Figures 4, and 7, each disk comprises a hub 37 secured to the associated motor shaft end by a set screws 38, a radially extending web portion 39, and a cylindrical, axially extending peripheral part iii. The part 48 is formed alternately with grooves 41 and ridges 42 which are deployed axially with respect to the motor shaft 23. Radial holes 43 extend from the inner surface of the part it? to the bottoms or roots of the grooves 4.

In operation, when the disks are driven in the direction of the arrow a (see Figs. 1 and 7), the portions of the disks passing through the liquid in the receptacle 17 will pick up liquid which will adhere to the outer and inner surfaces of the peripheral disk parts 449, the bottoms and radial walls of the grooves 41, and the walls of the radial holes 43. Portions of the disks with liquid adhering to these numerous surfaces will then turn through the air above the level of liquid in the receptacle 1'? so as centrifugally to throw the liquid into the duct A. Liquid adhering to the outer surfaces of the peripheral parts 453' will be thrown ofi first so as to cause a dispersion or diffusion of liquid immediately to the left of the fan C. Liquid adhering to the wall parts of the radial holes 43 will work outwardly progressively until it reaches the outer surfaces of the peripheral part as, and will then be hurled ofi centrifugally so as to create a diffused fog or mist more to the left of or down stream with respect to the fan C. Still later, liquid adhering to the cylindrical inner face part of the peripheral part 40 will find its way to the radial holes 43, and will then move outwardly through these holes so as to finally be thrown centrifugally in the direction of air how in dispersed or difiused form, and will be deposited upon the coils 11 of the heat exchanger B in the form of thin films which will be evaporated in the manner previouslydescribed. Although liquid picked up by the disks 36 is thus thrown ofi generally in three-time phases, in the practical operation of the apparatus, there is no sharp line of demarcation b tween any of the successive phases. Instead, there is a gradual merging or transition from one phase to the other so that in effect there is a continuous or steady throwing off of liquid throughout substantially the whole travel of the unsubmerged parts of the disks.

It is desirable to control or regulate the zone within which the liquid dispersion or diffusion is produced, particularly in order to prevent throwing of liquid directly against the fan C instead of into the air stream on the down-stream side of the fan. in accordance with the in vention, such control may be accomplished through the provision of adjustable deflector means comprising arcuate deflector bands or strips generally designated 44. As shown particularly in Figure 7, each deflector disk extends arcuately and concentrically with respect to the axis of rotation of its associated dispersing disk 56, and has a part 44 projecting above the associated pan 17. The remaining part of the deflector 4 5 extends down into the pan and below the disk 36 where it is supported on an arcuate guide 55, and is hel in place by screws 46 extending through guide slots The heads of the screws 46 are adapted to be screwed against the guide d5 adjacent the walls of the slot 3? so as to lock the deflector in adjusted position. Preferably, the deflector 4 3 is channel-shaped in cross section and, as shown in Figure 9, comprises a web part and inwardly extending side flanges 49.

The deflector i4 is so positioned with respect to the associated disk 36 that its portion 44 extending above the pan 1'7 enshrouds the periphery of the disk immediately above the point at which the disk leaves or emerges from the liquid in the receptacle 17. Accordingly, liquid which otherwise would be nrown centrifugally toward the air-entrance end of the duct A, is intercepted or blocked by the deflector part 44 thus confining the diffusion space or zone to the down-stream side of the fan C.

improved equipment is provided for controlling the operation of the fan motor d, and the disperser motor 20, and the supplying of evaporative liquid to the tank or reservoir 4, all in dependence upon atmospheric conditions. Figure 10 shows schematically a control arrange ment particularly suited for use in localities in which there is a wide range of outside air temperatures, that is, in localities in which the summer temperature is high enough to make it necessary to disperse evaporative fluid in the duct A for efficient operation, and in which in winter the temperature is below freezing or is low enough to product a sufficient cooling efiect without its being necessary for the disperser to operate.

Figure 10 shows a part of a building wall St), the inner surface 50* of which faces a room or an enclosure housing 'the apparatus disclosed in Figures l9 inclusive, and the outside surface Ed of which is exposed to outside air temperatures. One conductor 51 of an electrical power line leads through a normally clos..d relay or solenoidoperated switch 52 to one side of each of the motors 5 and 2t"; which operate the fan C and the disperser unit D respectively. The other conductor of the power line leads through a conductor to the other side of th fan motor 5. A main control switch generally designated 55 is interposed in the power line. When switch is closed the fan motor 5 will operate continuously irrespective of atmospheric temperatures outside of building.

The disperser motor 29 will operate only when the side temperature is sufficiently high to require the persing or evaporative fluid in the duct A to produce desired cooling effect. in most localities this condition will obtain throughout most of the year and may therefore be considered the normal operating condition. In order that the disperser motor 20 may be stopped when the outside air temperature reaches a predetermined low point and may automatically be started when the outside temperature rises above that point, a conductor 56 is led from the motor 29 to a normally closed micro-switch 57, and a conductor 55 is led from the switch 57 to the power line.

close the make-up valve 62.

r V V power line conductor 53. A thermostat,'comprising a bulb or container h for expansible gas located outside the wall'Stl and sylphon bellows on the insideofv the wall, is provided for pressing upon an operating arm or bar 61 and maintaining the switch 57 closed when the outside air temperature is above the predetermined point. In operation under normal conditions the expansible gas in the thermostat device 596t) being heated above the predetermined outside temperature will expand the bellows 6 so as to maintain the switch 57 closed. 7 Under these conditions a circuit will be completed through the power line conductor 51, the switch 52, the motor 20, the conductor 56 the closed micro-switch 57, the conductor 58, and the power line conductor 53 so that the disperser motor 20 will operate. If, however, the outside temperature should fall below the predetermined point, the gas in the thermostatic device 59-6ii will contract, the bellows 6% will collapse, and the micro-switch 57 will open so as V to break the disperser motor circuit, the fan motor 5, however continuing in operation. i i

' Means isprovided for automatically efiecting the addition of water to the tank or reservoir 4 in order to maintain 'a substantially predetermined level therein. in the embodiment of the invention shownin Figures l to 10 inclusive, a solenoid-operated valve 62. is positioned to discharge make-up evaporative fluid into the tank d. The circuit for operating the solenoid valve 62 includes the conductor 5% leading from the power line to one side of the solenoid, a conductor 63 leading from the other side of the solenoid to a normally open micro-switch 64, a conductor 65 leading from the micro-switch 64 to the conductor se the normally closed micro-switch 57, and the conductor 58 which leads to the conductor 530i the When the liquid in the tank 4 is at a predetermined operating level, the micro-switch64 will remain open so that the valve 62 will not be opened to discharge, make-up liquid into the tank. When liquidis lost' or consumed in the cooling operation the level in the tan; 4 will permitting lowering of a float 66 and rocking of a shaft 67 and a cam 68 which causes the switch as to be closed. This will energize the solenoid, causing the valve 62 to open and discharge make-up liquid into the tanit i until rising of'the float 65 returns the earn 68 to its normal position in which the micro-switch 64. will be opened so as to de-energize the solenoid and When the apparatus is operating under normal conditions, that is, when the outside temperature calls for operation of the disperser unit D, it is desirable that the entire apparatus be placed out of operation or that a warning signal be operated in the event that the supply of evaprative liquid fails. To this end a normally closed microswitch 69 adapted to be opened by a cam '79 on the float rock shaft 67 is provided for controlling the normally closed relay or switch 52 previously referred to. 'As shown in Figure 10, a conductor 71 leads from the power line conductor 53 through the normally closed control switch 6%, a conductor 72, the coil of the relay 52, and a t the power line conductor 51. If the conductor :3 to liquid in the tank 4 should fall'belo-w a predetermined level, the lowering of the float 66 and rocking of the cam 7 motor as, the normally closed micro-switch 57 in circuit with the solenoid valve 62will be open and therefore the valve will not be operated automatically to supply makeup liquid to'the tank 4 to take the place of liquid which .irom the heat exchanger.

islost by surface evaporation caused by the relatively high temperature in the room or enclosure in which the apparatus is located. Consequently, after the apparatus has been in operation under such conditions fora short while,

' the float 66 will descend, causing the micro-switch 69 to be opened in the manner described above. In order that the opening of the switch 69 under these conditions will not stop the operation of the whole system, which would i be undesirable, a normally open micro-switchfi'i' is shunted across the micro-switch 69 by means of conductors 75 and 76. Under cold weather conditions the contraction of the bellows 6i) and operation of the arm 61 causes the control switch 74 to close, thereby main:

1 taining the coil of the relay switch 52 energized irrespective of whether the float-controlled switch 6? is open or closed. Thus, when the switch 74 is open, the switch 69 is conditioned for operation by the float :36 to tie-energize the relay coil 52, but when the switch 74 is closed, the

switch 69 is'not conditioned for effective operation.

Figure 10 shows the control equipment only schemati tially straight horizontal duct MEGA in which are mounted a heat exchanger 10 .33, a fan 169C, and a liquid disperser The parts are so ar ranged that the fan ltd-3C, located adjacent the right hand unit generally. designated llidD.

end of the duct as viewed Figures 11 and 12, cansesa stream of air to flow through the duct past the air chaniber immediately above the disperser unit i i-hill), over".

and through the heat exchanger 19933, the air then passingout through the left hand end of the duct be fore the air encounters the heat exchanger 1 cooled by evaporative liquid thrown upwardly and dis-.

persed or diiiused by the disperser will) so as more e trvely to extract heat from the heat exchanger Preferably, the action of the disperser 16103 is so regus lated or controlled that, in addition to producing a volume,

of diffused liquid between the fan'iiiltlC and the heat ex.-

changer 1963, it also deposits a veryjthin film of liquid upon the'surfaces of the heat exchanger 1 MB so asfto' augment the cooling operation by evaporation of liquid drops or globules of evaporative liquid are caused constantly to impinge upon the upper part of the heater,- changer 1MB from which they run down over intermediate and lower parts of the heat exchanger so-"as to 1 maintain the heat exchanger constantly washed and free from scale and foreign matter which'otherwise would interfere with the eflicient transferringof heat.

The duct it'itlA may be of any suitable construction, and in the form shown in Figures 11 to 23 it is constructed of sheet metal suitably'reinforced at its seams and corners. A screen 192' of wire mesh or equivalent material is mounted at the intake end of the duct for preventing the entrance of particles of solid foreign matter. A 'mat or filter 1030i fibrous material isrnounted at the left hand end of the duct for preventing the outflow or" any unevaporated droplets of liquid. which may be carried in the t air stream past the heatexchanger 14KB.

mat 1% is so positionedth'at droplets or"- liquid which it. 70 intercepts will drainbaclc into a pan or reservoir res The filter or mounted in the bottom of the duct ltltlAQ The fan C is arranged to be driven an electric' motor 195 mounted upon a support comprising a plat form 1496 carried by legs 167 extending upwardly from the bottom of the. pan J04;

it is Additionally, relatively large' A partition res extending across the duct in the central plane of the fan 1696 is,

formed with an opening 198* which receives the fan blades with suitable operating clearance.

The heat exchanger lfifiB comprises a condenser tube or coil unit having an inlet connection it)? adatped to be connected to a source of gas or other fluid medium to be coole and to lead such medium to a top header 119 which may be constituted by the left end of the pipe or connection Extending from the top header 110 are ten pipes formed respectively as cells, the pipes 111i extending back and forth so as collectively to cover the major part of a cross section of the duct EMA, the lower parts of pipe Elli ending at and being connected to a bottom header 112. Fluid cooled by passage through the pipes 112i flows from the bottom header 112 through a pipe bend 7113 (Figure 13) into a horizontally disposed supplemental heat exchanger or cooling unit 114 which is located directly under the coil assembly 111. Fluid which has been cooled in the pipe coils 111 and the supplemental heat exchanger 114 is discharged through an exit pipe lid.

in operation, fluid to be condensed or cooled is introduced through the inlet 169 into the heat exchanger ltlllB so as to flow first through the coils 111 in which it is cooled by air forced through the duct 100A by the fan 1680. Under certain load conditions the cooling efiect of the air alone may be suificient to bring about the desired condensing or cooling of the fluid passed through the heat exchanger 1013B.

Under heavier load condiu'ons, when a greater cooling effect is desired, the disperser lilllD is operated to create a mist or fog of dispersed or diffused evaporative liquid in the stream of air approaching the heat exchanger teen, and so as to deposit a film of evaporative liquid on the coils 111, and to cause relatively large drops of liquid to impinge upon the top part of the coils 111 so as to maintain the entire heat exchanger 199B washed. Evaporation of the liquid in the air stream cools the air itself so as to render its heat absorptive capacity greater; and evaporation of the film of liquid from the coils 111 still further augments the cooling capacity.

The surplus evaporative liquid e. g. water, discharged by the disperser 106D and dropping, unevaporated, from the coil assembly 111, and from the duct space in which the coil assembly 111 is mounted, will envelop the supplemental cooler 11 and extract additional heat from the medium flowing from the coil unit 111 through the supplemental unit 114.

The dispersing apparatus 109D which performs the important function of creating a graduated dispersion of liquid varying progressively from relatively large drops cast upon the upper part of the unit ltltlB to a finely diffused fog or mist caused to envelop the intermediate and lower parts of the coil assembly, is constructed as a unit which can be manufactured and assembled in a factory where the necessary care can be given to assembling the parts in their proper relationship. The unit lllllD can then be easily mounted Within the duct 100A when the Whole apparatus is set up or assembled either in an assembly plant or on a construction job location.

The dispersing unit 169D includes a base structure generally designated 116 mounted upon a stand or bracket comprising channel supports ll -(Figure 14) secured in any suitable manner to the bottom of the pan 1&4. The base structure includes two open top receptacles 117 respectively connected to an intervening motor housing 113 by screws 119. A motor 120 is mounted within the housing 113 and has its shaft 121 journalled in motor bearings 122 and projecting through bearings 123 fitted in openings 124- in the end walls 125 of the housing 118. The weight of the motor is carried by its shaft 121, supported in the bearings 123. Rotation of the motor stator is prevented by engagement of motor stator clamping screws 12 in tapered slots v125 in lugs 125 on the upper and lower halves 118 and 118 of the housing 118.

The housing 113 is filled, or nearly filled with liquid dielectric, e. g., good quality insulating oil indicated at 126 in suflicient quantity to surround the motor 126) completely, and substantially fill the motor casing, having ingress thereto through a hole 127 through which wires extend outwardly from the motor windings, and other holes (not shown) with which the motor casing may be provided. The wires or conductors 128 leading from the motor windings outwardly through the hole 127 into the housing 11% pass outwardly through the housing through a fitting 129 at the lower end of a tube 130 which may be constituted by a flexible hose, the upper end of which extends into a junction or control box 131 as shown in Figure 12. Also leading into the junction or control box 131 is a power supply cable 132 and a conductor cable 1312 which extends to the fan motor 1135 The outer housing 118 is constituted by an upper half section 318 and a lower half section 1118 connected together by bolts 118. In assembling the disperser unit 1891), the upper section 118 is removed, the motor 120, the bearings 123 and seals 123 are inserted into the lower section 118 and the conductors 128 are led outwardly through the fitting 129 and the hose 136. Then the upper section 118 is bolted down on the lower section 118 If desired, the separate motor casing may be omitted, in which case the motor field coils may be mounted directly on the housing 113, and the armature supported by its shaft extending through the bearings 123 carried by the housing 118. The dielectric 126 may be introduced into the housing through the opening therein which receives the fitting 129, or, with the upper end of the hose 13%) positioned at a level substantially above that of the housing 118, liquid dielectric may be poured down through the hose 13% so as to till the housing 118 and to extend partially upwardly through the hose 13% the upper level of the dielectric standing in the hose 130 being below the upper end of the hose.

In operation, the dielectric oil fills the casing of the motor 120 and surrounds and covers the motor rotor and stator windings, so as to transfer the heat generated by the motor to the dielectric 126 included in the space between the motor casing and the housing 118. Although this provides for very eflicient cooling of the motor, continued operation under even reasonably heavy load conditions necessarily will result insome temperature rise in the motor and in the dielectric oil 126, causing the latter to expand somewhat. Expansion of the oil can take place without creating pressure in the housing 118, since the oil may rise slightly within the hose 130. Conversely, when the motor cools, the consequent cooling and contraction of the dielectric 126 will not produce any vacuum within the housing 113, because when the dielectric cools and contracts it will be replenished by oil descending from the hose 139.

The receptacles 117 are formed with side openings 135 so positioned as to be below the level of the evaporative liquid in the pan 1% when the dispersing unit litlQD is mounted in the pan as shown in Figure 12, thus ensuring that liquid from the pan 104 will flow into the receptacles 117 so as to maintain them filled to substantially the same level as the level of the evaporative liquid in the pan. The evaporative liquid is picked up from the receptacles 117 and thrown transversely with respect to the direction of air flow, and also generally in the direction of air flow by impeller means comprising disks 13% mounted respectively on the opposite ends of the shaft 321 and extending below the tops of the receptacles 117, so that the bottom portions of the disks will be partly submerged or immersed in evaporative liquid in the rcceptacles. The motor 129 drives the disks in the direc tion of the arrow :1 in Figure 12 at such high speed as to throw the evaporative liquid vertically into the duct 109A, and also generally in the direction of flow of air, that is, from right to left as shown in Figure 12. The disks 136 are so formed as to produce a graduated dispersion of drops, and fog or mist of evaporative fluid or against the fan.

11 with some droplets; of such size asnot to be immediately evaporated. A sufticient quantity of droplets of unevapoa rated liquid is thrown against the upper part'of the heat exchanger unit 1993 to insure. that liquid draining-down over the coils in the unit 190B will maintain the coils thoroughly washed and free of adhering solid impurities and scale.

Preferably, the disks 136 are mutually balanced and are of identical form. Each disk comprises a hub 137 secured to the motor shaft 121 by a set screw 138, a radially extending web portion 139, and a cylindrical, axially extending peripheral part 149. The part 140 is formed alternately with grooves l llv and ridges 1:22 which are deployed axially with respect to the motor shaft 121. Radial holes" 143 extend from the inner surface of the part 149 to the bottoms or roots of the grooves 141.

V In operation, when the disks are driven in the direction of the arrow a in Figure 12, the portions of the disks passing through the liquid in the receptacles 117 will pick up liquid which will adhere to the outer andinner surfaces of the peripheral disk parts 149,. the bottoms and radial walls of the grooves, and the wallsv of the radial holes 143. Portions of'the disks with liquid adhering to these numerous surfaces will then turn through the air above the level of liquid in the receptacles 117 so as to throw the liquid centrifugallyinto the duct liitlA. Liquid adhering to the outer surfaces: of the peripheral parts 14% will be thrown ofi first so as to cause a dispersion or diflus'ion of liquid immediately tothe left ofthe fan 100C. Liquid adhering to the wall parts of the radial holes 143 will work outwardly progressively until it reaches the outer surfaces of the peripheral partl'dti, and will then be hurled ofl centrifugally so as to create a difiused fog or mist more to the left of or downstream with respect to the fan 109C. Still later, liquid adhering to the cylindrical inner face part of the peripheral part 140 will find its way to the radial holes 143, and will then move outwardly through these holes so as' finally to be thrown centrifugally in the direction of air flow in dispersed or diflused form. The diffused liquid will then be deposited" upon the coils 111 of the heatexchanger 1968 in the form of thin filmsiwhich will be evaporated that, in effect, there is a" eontinuousor steady throwing off of liquid throughout substantially the whole travel of the unsubmerged parts of the disks.

in order to control the zone within which'the liquid dispersion or diffusion is produced, particularlyin' order to prevent throwing of liquid directly against the fan 160C instead of into the air stream on the downstream sideof the fan, the bottom of each receptacle 1'17is" formed to serve also as a deflector 144 having a lip 145 adjacent the portion of the associated disk which is running out of the receptacle 117, the lip projecting slightly above that portion" of the disk. The lip is so positioned with respect to the associated disk. 136 as to permit evaporative liquid to be' thrown upwardly and downstream at an inclination toward the upper part of the heat exchanger 1033 without permitting liquid to be'thrown directly upwardly'against thetop of the duct The bottom of each receptacle 117 may also be formed with a lip 146 located adjacent the downgoing side of the; associated disk for deflecting evaporative liquid thrown oil? by the disk into the receptacle 117 instead of permitting the liquid to be thrown onto the surface of, liquid in the pan 194. Generally stated, the deflectors 144 a'ct similarly to the deflectors a t-described with reference to the construction shown in Figures 1 to 10 except that the deflectors 144 are not 12 adjustable. In some instances it is advantageous to be able to adjust the deflectors 44, butin most cases it is advisable to ha e the deflectors set or built in the most A advantageous position with respect to the disperser disks at the factory, and not to provide any means for adjustment which may be tampered with by one inexperienced in the adjustment of such equipment.

A particular feature of the construction shown in Figures 11 to 23 is the provision of a plurality of vanes 147 secured to the underside of the top of'the duct 100A for spreading the .diiiused evaporative liquid laterally over the heat exchanger unit 10593. As shown in Figures 13 and 15, the vanes are so positioned that evaporative liquid thrown off by the disks 136 will be .de

flected outwardly towards the sides of the duct 100A, ensuring that the side portions of the pipe coils 111 will not be starved for cooling and washing. The liquid thrown ofi by the two disks 136 spreads laterally to V debris.

tions of the coils 111 of the center of the duct to approximately the same extent as the coil portions directly in front of. the disks 136. Consequently, the vanes 147 are so positioned as not to deflect liquid inwardly toward the center of the duct. It is important, however, that the vanes diverge so asto guide or deflect the liquid la'tQ erally outwardly to provide ample liquid adjacent the sides of the duct 160A. The vanes. also direct washing liquid toward the outlet end of the duct 100A 'to ensure drainage of liquid over the coils 111 between the rightmost coil, as viewed in Figures 'll a'nd' l2, and the" coil adjacent the filter or eliminator 103, thus ensuring that all of the coil elements will be kept washedclean.

The apparatus disclosed in Figures 11 to 23 inclusive may be provided with control means of the kind illustrated in Figure 10. The control equipment may be modified. to suit conditionsor manufacturing costs. For example, there may be provided afloat 166 for directly operatingafloat controlled make-up valve 1665f0rcon: trolling. the admission of evaporative liquid from a sup-- ply line 166 tomaintain the liquid at the proper level in the pan 104.

The construction shown in Figures 11' to--23 also in cludes.. means. for ensuring against the over-flowing of the pan..14- the float valve should-- fail properly to cut ofithe supplythrough the pipe 166, andalso to keep the surface of: the liquid in the pan104 free of buoyant debrisr' Asshownin Figure 12,;a drain pipe 167 is;

equippedwith a funnel shaped skimmer 168 having an openupper end of substantial areain a horizontal plane I and-at a levelabout one-eighth inch above the normal liquid level maintained in the pan lfl4nby the float valve. The arrangement is such that some of the Water thrown off bythe disperser unit will rain into the skimmer, and will be drained ofi, carrying with it buoyantdebris. If. the'float valve should fail to close, the skimmer would drain ofi surplusliquid, and prevent overflowing inthe pan 164. By unscrewing the skimmer 16 8,the-pan'may be drained. Normally, the skimmer drains oflonly the liquid which falls into it from the difiused liquid thrown ofi by the disperser unit, and unnecessary wasting of' liquidis'prevented. However, the normal removal of liquid through the skimmer is sufficient to maintain the liquid in the system substantially free from buoyant The constructions illustrated embody the invention in preferredforms, butit is intended that the disclosure be illustrative rather than definitive. The invention is defined inthe appended claims.

I claim:

1. In a liquid dispersing unit, an" open-top liquid receptacle; a disk mounted to rotate about a horizontal axis extending across said receptacle, a lower portion only of said disk extending down into said receptacle for immersion in liquid therein, said disk comprising a radially extending portion, and a perforated cylindrical peripheral portion extending axially from said radially extending portion and defining a cylindrical chamber open at one end to permit entrance of liquid freely within said cylindrical peripheral portion, said cylindrical portion being formed with alternately arranged, axially deployed grooves and ridges.

2. In a liquid dispersing unit, an open-top liquid receptacle; a disk mounted to rotate about a horizontal axis extending across Said receptacle, a lower portion only of said disk extending down into said receptacle for immersion in liquid therein, said disk comprising a radially extending portion, and a cylindrical peripheral portion extending axially from said radially extending portion, said cylindrical portion being formed with alternately arranged, axially deployed grooves and ridges, and with openings extending radially through said cylindrical portion from the bottoms of said grooves to the inside or" said cylindrical portion.

3. In evaporative condenser apparatus, an air duct; a heat exchanger mounted in said duct and extending transversely and vertically therein; means for causing a stream of air to fiow through said duct and in contact with and past said heat exchanger; an open top liquid reservoir means in said duct positioned upstream with respect to the direction of air flow; a disperser disk mounted to rotate about a horizontal axis extending across said reservoir, a lower portion only of said disk extending downwardly into said reservoir for immersion in liquid therein, said disk having a radially extending portion and a cylindrical peripheral portion extending axially from said radially extending portion, said peripheral portion being formed with alternately arranged circumferential grooves and ridges adapted, when said disk is rotated at high speed, to throw oft" liquid in successive but merging phases so as to produce within said duct a liquid distribution varying progressively across said duct from a dispersion of relatively large drops which are thrown against the upper part of said heat exchanger to a finely diifused fog or mist which is caused to envelop the lower part of said heat exchanger whereby substantially the entire heat exchanger will be maintained wet and liquid from said drops will run down and over and thereby will wash the surfaces of said heat exchanger from top to bottom thereof; and a motor for driving said disk at a speed sufficiently high to produce the so characterized iiquid distribution.

4. In evaporative condenser apparatus, an air duct; a heat exchanger mounted in said duct and extending transversely and vertically therein; means for causing a stream of air to flow through said duct and in contact with and past heat exchanger; an open top liquid reservoir means in said duct positioned upstream with respect to the direction of air flow; a disperser disk mounted to rotate about a horizontal axis extending across said reservoir, a lower portion only of said disk extending downwardly into said reservoir for immersion in liquid therein, said disk having a radially extending portion and a cylindrical perpheral portion extending axially from said radially extending portion, said peripheral portion being formed with a plurality of circumferentially and axially deployed openings extending through said peripheral portion, whereby said disk is adapted when rotated at high speed, to throw off liquid in successive but merging phases so as to produce within said duct a liquid distribution varying progressively across said duct from a dispersion of relatively large drops which are thrown against the upper part of said heat exchanger to a finely diffused fog or mist which is caused to envelop the lower part of said heat exchanger whereby substantially the entire heat exchanger will be maintained wet and liquid from said drops will run down and over and thereby will wash the surfaces of said heat exchanger from top to bottom thereof; and a motor for driving said disk at a speed sufiiciently high to produce the so characterized liquid distribution.

References Cited in the file of this patent UNITED STATES PATENTS 1,269,909 Cooper June 19, 1918 1,667,291 Lavett Apr. 24, 1928 2,064,271 Schmidt et a1. Dec. 15, 1936 2,091,159 Persons Aug. 24, 1937 2,215,753 Goodman et al Sept. 24, 1940 2,448,297 Christensen Aug. 31, 1948 2,571,069 Shearman Oct. 9, 1951 

